METHODS OF KAT UKSJ EUCTION. 239 



Severn! years, is now, so far as we can make out, no longer being^ 

 manufactured. The latter trap, known to us as the Brailsford 

 Trap, consists of a long, narrow wire cage with doors at each end, 

 wliicl), when the trap is set, remain open, leaving a dii^ect passage 

 through. A platform in the centre, where the bait is placed, is 

 connected by a spring which when trodden upon releases the 

 doors, imprisoning the rat or rats. Such traps were put down 

 on 687 occasions and accounted for the capture of 209 rats. Two 

 makes of this trap were formerly sold, the one in which the 

 height of the passage measured 4| inches, the other in which it 

 measured 7 inches. As the latter gave far better results than 

 the former, in oi'der to ascertain the propoi'tions which Avould 

 give the best results, traps of different height and width were 

 tested, with the result that the type with the greatest height 

 was ioun<l most successful. 



The following are particulars of these tests : — 



Percentage of rats caught in traps 4.^" high 19. 



n :i )5 5> ' ij 28. 



)! 55 JJ J> " )? «34. 



The width, provided it allows for the free passage of the rat, 

 makes no difference. 



Other cage-traps tested included such well-known types as the 

 ordinary Cage Trap with bait hook, and with a platform con- 

 nected by a spring with the door, the Eelpot or AVonder, the 

 Round Wire, and the " Mysto." We also experimented with a 

 number of new types sent to us, and with Barrel traps and 

 Stockades. 



The ordiaary Cage Trap. — This trap, which is sold at most 

 ironmonger shops, we saw iu use on many occasions in the course 

 of our visits to rat-infested localities, but were invariably in- 

 formed that it caught no I'ats. This was likewise our experience 

 with the type without the bait-hook. \^ hen, however, it was 

 provided Avith the platform which when trodden on closed the 

 door, more satisfactory results were obtained, 16 rats being 

 caught with 166 of these traps. 



The Eelpot or Wonder 7Vap, which permits the free entry of 

 the rats whilst preventing their exit, is divided into two com- 

 partments connected with a trap-door. This trap has, I know, 

 frequently been responsible for the capture of numbers of rats. 

 With us it did not prove a great success. The keeping of a 

 female in the trap and baiting with the female genital organs 

 having been said to entice the males, both these devices were 

 resorted to, but with negative results. 



The Round Wire Trap is a simple type, tlie rats having an 

 entry thi-ough a hole in the centre, but being prevented from 

 escaping by the presence of a number of fine loose wires which 

 hang from the sides of this apei;ture and close round the hole 

 when tlie rat climbs up in order to escape. For some weeks we 



